Python bitwise operators

« Left Shift

Moves the bits of its first operand to the left by the number of places specified in its second operand.

Formula: $a « n = a * 2^n$

• Shifting a single bit to the left by one place doubles its value.
• Shifting to two places to the left by one place quadruple its value.

>>> 100 << 1
200
>>> 100 << 2
400
>>> 100 << 3
800

» Right Shift

• The rightmost bits always get dropped.
• Every time you shift a bit to the right by one position, you halve its underlying value.

Formula: $a » n = [a/2^n]$

>>> 100 >> 1
50
>>> 100 >> 2
25
>>> 100 >> 3
12
>>> 5 >> 10
0

• the right shift operator automatically floors the result.

>>> 5 >> 1  # Bitwise right shift
2
>>> 5 // 2  # Floor division (integer division)
2
>>> 5 / 2   # Floating-point division
2.5
>>> -2 >> 5
-1

& Operator

0 & 0 = 0
0 & 1 = 0
1 & 0 = 0
1 & 1 = 0

For numbers:

27 & 23

1. Covert to binary

   27 -> 11011 23 -> 10111

2. turns to (in binary)

   11011 & 10111 = 10011 -> 19

   27 & 23 = 19

Resources

• https://realpython.com/python-bitwise-operators/